9,739 research outputs found
Indianapolis-Marion County City-County Council: A Study of Council Effectiveness
The purpose of this research is to measure and assess the effectiveness of the Indianapolis-Marion County City-County Council. Given that effectiveness may be defined in a number of ways, the research conducted includes many types of information that can provide a well-rounded assessment of the council
Social Equity and COVID-19: The Case of African Americans
Emerging statistics demonstrate that COVID-19 disproportionately affects African Americans. The effects of COVID-19 for this population are inextricably linked to areas of systemic oppression and disenfranchisement, which are further exacerbated by COVID-19: (1) healthcare inequality; (2) segregation, overall health, and food insecurity; (3) underrepresentation in government and the medical profession; and (4) inequalities in participatory democracy and public engagement. Following a discussion of these issues, this article shares early and preliminary lessons and strategies on how public administration scholars and practitioners can lead in crafting equitable responses to this global pandemic to uplift the African American community
Three `species' of Schr\"odinger cat states in an infinite-range spin model
We explore a transverse-field Ising model that exhibits both spontaneous
symmetry-breaking and eigenstate thermalization. Within its ferromagnetic
phase, the exact eigenstates of the Hamiltonian of any large but finite-sized
system are all Schr\"odinger cat states: superpositions of states with `up' and
`down' spontaneous magnetization. This model exhibits two dynamical phase
transitions {\it within} its ferromagnetic phase: In the lowest-temperature
phase the magnetization can macroscopically oscillate between up and down. The
relaxation of the magnetization is always overdamped in the remainder of the
ferromagnetic phase, which is divided in to phases where the system thermally
activates itself {\it over} the barrier between the up and down states, and
where it quantum tunnels.Comment: 7 pages, added numerical result
Global Dynamics in Galactic Triaxial Systems I
In this paper we present a theoretical analysis of the global dynamics in a
triaxial galactic system using a 3D integrable Hamiltonian as a simple
representation. We include a thorough discussion on the effect of adding a
generic non--integrable perturbation to the global dynamics of the system. We
adopt the triaxial Stackel Hamiltonian as the integrable model and compute its
resonance structure in order to understand its global dynamics when a
perturbation is introduced. Also do we take profit of this example in order to
provide a theoretical discussion about diffussive processes taking place in
phase space.Comment: Accepted A&
Black Hole Motion as Catalyst of Orbital Resonances
The motion of a black hole about the centre of gravity of its host galaxy
induces a strong response from the surrounding stellar population. We treat the
case of a harmonic potential analytically and show that half of the stars on
circular orbits in that potential shift to an orbit of lower energy, while the
other half receive a positive boost and recede to a larger radius. The black
hole itself remains on an orbit of fixed amplitude and merely acts as a
catalyst for the evolution of the stellar energy distribution function f(E). We
show that this effect is operative out to a radius of approx 3 to 4 times the
hole's influence radius, R_bh. We use numerical integration to explore more
fully the response of a stellar distribution to black hole motion. We consider
orbits in a logarithmic potential and compare the response of stars on circular
orbits, to the situation of a `warm' and `hot' (isotropic) stellar velocity
field. While features seen in density maps are now wiped out, the kinematic
signature of black hole motion still imprints the stellar line-of-sight mean
velocity to a magnitude ~18% the local root mean-square velocity dispersion
sigma.Comment: revised version, typos fixed, added references, 20 pages MN styl
Cusp Disruption in Minor Mergers
We present 0.55 x 10^6 particle simulations of the accretion of high-density
dwarf galaxies by low-density giant galaxies, using models that contain both
power-law central density cusps and point masses representing supermassive
black holes. The cusp of the dwarf galaxy is disrupted during the merger,
producing a remnant with a central density that is only slightly higher than
that of the giant galaxy initially. Removing the black hole from the giant
galaxy allows the dwarf galaxy to remain intact and leads to a remnant with a
high central density, contrary to what is observed. Our results support the
hypothesis that the persistence of low-density cores in giant galaxies is a
consequence of supermassive black holes.Comment: 5 pages, 2 postscript figures, uses emulateapj.sty. Accepted for
publication in The Astrophysical Journal Letter
What Makes an Organization Public? Managers’ Perceptions in the Mental Health and Substance Abuse Treatment System
The question “What makes an organization public?” is a leading point of scholarly inquiry in the field of public administration. This study supplements existing theory on publicness by further exploring the primary influences on an organization’s publicness—influences identified by analyzing data from in-depth interviews with senior-level managers of mental health and substance abuse treatment facilities. Results from a grounded theoretical analysis of these managers’ perceptions provide support for a conceptual framework of organizational publicness in which political authority, horizontal engagement, and public engagement are associated with higher levels of publicness. Better understanding of the prism through which senior managers conceptualize publicness may enhance managerial awareness of the most salient structural and institutional mechanisms that empower treatment facilities to effectively support individuals suffering from mental health disorders such as substance abuse, emotional distress, and depression
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